import java.util.Scanner;

public class Main {
    public static void main(String[] args) {
        int a=10;
        int b=20;
        swap(a,b);
        System.out.println(a);
        System.out.println(b);
    }
    public static void swap(int a,int b){
        int tem=a;
        a=b;
        b=tem;
    }
    public static void main3(String[] args) {
        Scanner sc=new Scanner(System.in);
        String str=sc.nextLine();
        String[] arr=str.split(" ");
        System.out.println(arr.length);
    }
    public static void main2(String[] args) {
        Scanner sc=new Scanner(System.in);
        String str=sc.nextLine();
        int index=str.lastIndexOf(" ");
        String st=str.substring(index+1);
        System.out.println(st.length());
    }
    public static void main1(String[] args) {
        Scanner sc=new Scanner(System.in);
        String str=sc.nextLine();
        String[] str0=str.split(" ");
        int i=str0.length;
        char[] ch=str0[i-1].toCharArray();
        System.out.println(ch.length);
    }
}